US AI firm Harvey builds legal AI on China's Kimi K3 model

Harvey, a legal tech company in San Francisco, said its new model, Harvey Tenet, was built by fine-tuning Kimi K3, an open-weight model from China's Moonshot AI, for complex legal tasks. Previously, Harvey customized closed models from Anthropic, OpenAI, and Google. This shift shows Western tech firms are turning to Chinese open-weight models. Harvey says the model beats its base model and US frontier systems like Fable 5 and GPT-5.6 Sol on complex legal tasks, and cuts costs. Training took two months using about 150 Nvidia B300 GPUs. AI policy researcher Simon Hedlin called it a great example of open-weight value, but noted the US is falling behind in frontier open-weight development. Harvey was founded in 2022 and was valued at $11 billion in March.